Woktenna for 3G

After looking for inexpensive external antennae I came upon a great thread on Whirlpool describing how to make your own. I also wanted a better way to measure the signal strength while I point the dish, and found this page detailing the AT commands for the Optus/Huawei E169.

On a spare Sunday afternoon I put it all together, and to my surprise, it works exceptionally well!

With the dongle plugged into my computer I rarely get a 3G service.  With this woktenna I get 4-5 bars of 3G.  The best I've got is number 13 or -87dBm, a workable connection with 5 bars solid.

Parts:

  • One Mesh fruit bowl from Myers $30
  • One Active USB cable (5m)  from Jaycar $14.95
  • One Paper Towel Holder from a bargain shop $2
  • One beer coaster
  • An old speaker mounting bracket
  • Scraps of aluminium, bike parts and a drink bottle lid.

 

 

 

 

The focal point of the dish is 190^2/(4*105) = 85.95mm.  This is just shy from the edge plane of the rim.

 

 

 

Here's a small ruby script that displays the signal strength directly from the Huawei E169.  It requires

sudo gem install ruby-serialport

 

 

#!/usr/bin/ruby

#puts "hi"

require 'rubygems'

require 'serialport'

require 'readline'

sp = SerialPort.new "/dev/tty.HUAWEIMobile-Modem", 38400

sp.read_timeout == 200


1000.times do

  sp.write "AT+CSQ\r\n"

  j1 = sp.readline

  t = Time.new.to_s

  puts "TIME: " + t + "SIGNAL: " + sp.readline

  sp.flush

  sleep(1)

end

#puts "ho"



7 thoughts on “Woktenna for 3G

  1. I don’t know about you, but my mum would be less than pleased with having that anywhere near where she lived.

    I suspect buying an actual wok may have been cheaper (unless fruit bowl was already in stock and surplus to requirements).

  2. Ha, well I was buying on parabaloid-ness not price. Not sure what the reaction will be. It could be described as “art”, which might fit in well there.

    It might have to be mounted outdoors, in which case I shall require a zip-lock bag of some sort and ANOTHER cable tie.

  3. How much speed increase did you experienced? Would there be a change if bigger bowl than this? And would there be a speed increase if I attack a radio type antenna to it or will it be harmful to the device?

  4. Gaurav, the main difference with using a larger dish is getting a better signal, which in turn can give you better throughput.

    You can’t really hurt the USB modem by attaching a larger antenna. This will help it receive a weak 3G signal. If the signal is too weak or there is too much noise then it will be hard to improve it. Certainly using a parabaloid dish like this instead of the built-in small antenna gives much better, directional, results.

  5. Greetings from South Africa…please tell me what material is the fruit bowl and beer coaster made? and where does the drink bottle lid go…I presume made of metal. Your help will be appreciated…….Regards